Closure for pressure vessels



7, 1956 M. P. WALL CLOSURE FOR PRESSURE VESSELS 5 Sheets-Sheet 1 Filed May 18, 19 53 INVENTOR Marion P. Wall BY Q ATTORNQ;

7, 1956 M. P. WALL CLOSURE FOR PRESSURE VESSELS 5 Sheets-s 2 Filed May 1 1953 VENToR Marion P. W BY Q 6" 7, 1956 M. P. WALL CLOSURE FOR PRESSURE VESSEL-S Filed May 18, 1953 5 Sheets-Sheet 5 M i v v v N INVENTOR Marion P. Wull BY i United States Patent CLOSURE FOR PRESSURE VESSELS 'Application May '18, 1953, SerialNo. 355,519

8 Claims. (Cl. 220-44) This invention relates to closures for access openings in pressure vessels and has specific relation to such a closure constructed in a manner to prohibit its being opened while a positive pressure exists within the vessel and to prohibit the building up of pressure within the vessel when the closure is not properly secured.

The invention provides a disc-like closure positionable, through suitable pivotal means, within a complementary seat means formed at the opening of a pressure vessel. The periphery of the closure plate is stepped to form an outwardly facing shoulder upon which is positioned a split ring that is expandable from a normally inoperative or contracted position to an operative position where it positively locks the closure plate within the seat means. Expansion of the split ring from its inoperative to its operative position is achieved by means of a dished element telescoped over the outer end of the closure plate and provided with a camming surface on its periphery which engages the inner surface of the split ring and is efiective to expand the split ring outwardly as the dished element is moved toward the closure plate. An exhaust passage extends through the closure plate and is controlled by a suitable valve means which is interconnected with the dished element in such a manner that as the valve is moved from its closed to its open position the dished element is moved away from the closure plate thereby allowing the split ring to contract to its inoperative position while as the valve moves from its open to its closed position the dished element moves toward the closure plate thereby expanding the split ring outwardly into its operative position.

It is the object of this invention to provide a closure of improved construction for use with pressure vessels which closure is positive in its action of preventing removal of the closure while a super atmospheric pressure prevails within the vessel and which includes means for relieving the pressure within the vessel.

Other and further objects of the invention will become apparent to those skilled in the art as the description proceeds.

With the aforementioned objects in view, the invention comprises an arrangement, construction and combination of the elements of the closure in such a manner as to attain the results desired as hereafter more particularly set forth in the following detailed description of an illustrative embodiment; said embodiment being shown by the accompanying drawings wherein:

Figure l is an elevational view showing the closure positioned within a seat provided at an opening of a pressure vessel.

Figure 2 is a side view taken generally from line 2-2 of Figure 1.

Figure 3 is a transverse sectional view taken along line 3-3 of Figure 2 and showing the closure in its locked position in the seat means.

Figure 4 is an enlarged fragmentary sectional view showing thesplit ring in its inoperative or disengaged position.

2,757,820 Patented Aug. 7, 1956 ice Figure 5 is a view similar to that of Figure 4 but showing the split ring moved to its operative or closure locked position.

Figure 6 is a sectional view similar to that of Figure 3 but showing a modified form of actuating means.

Figure 7 is a partial sectional view taken generally on line 7-7 of Figure 6 showing further details of the modified actuating means.

Figure 8 is an elevational view of the modified embodiment taken from line 8-8 of Figure 7.

Referring now to the drawings, wherein like reference characters are used throughout to designate like elements, seat means 10 forms a portion of an access opening for a pressure vessel and is flared slightly outwardly at its end for the reception of disc-like closure 12 therewithin. The closure 12 is pivoted to the wall of seat means 10 by means of arms 14 whichare secured at one end to closure 12 by bolts 16 and which have their other ends supported by shaft 18 from spaced brackets 20 extending outwardly from the wall of the seat means. When the closure is positioned within seat means 10 a fluid tight seal between the two is provided by gasket 17 which is partially received within a suitable groove formed in the closure.

The periphery of closure 12 adjacent the outer face thereof is relieved at 21 to provide inclined shoulder 22, Figs. 4 and 5, upon which is positioned split ring 24. Immediately opposite relieved portion 21 is groove or annulus26, formed on the inner face of seat means 10 and having a surface 28 parallel with shoulder 22 and spaced outwardly from the shoulder a distance slightly greater than the width of split ring 24.

, The split ring is constructed so that due to its own resiliency it is normally contracted to its extreme inner position as shown in Fig. 4 and when in this position it is entirely free from groove 26 permitting free withdrawal of closure 12 from seat means 10. When the split ring is expanded outwardly however, a portion of it moves into groove 26 whereby the ring is positioned between surface 28 and shoulder 22 thereby positively locking closure 12 within seat means 10.

Outward expansion of split ring 24 is effected by dished element 30 which is telescoped over the outer end of closure 12 and has camming surface 32 formed on its periphery for engagement with the inner surface of the split ring. The dished element is provided with enlarged openings 33 for the reception of the ends of arms 14 and is so constructed that when spilt ring 24 is in its inoperative position, i. e., fully contracted about relieved portion 21 as shown in Fig. 4, the rim of dished element 30 is positioned between the outer portion of split ring 24 and relieved portion 21. Thus, as dished element 30 is moved toward closure 12 camming surface 32 is effective to expand the split ring outwardly into its operative position intermediate surface 28 and shoulder 22 as clearly shown in Fig. 5.

I Actuation of dished element 30 to move it toward and away from closure 12 is had, in the embodiment of Figs. 1, 2 and 3, by stem 34 which is threaded in bore 36 provided inthe closure. The dished element 36 is received intermediate flange 38 formed on the stem 34 and flange 40 which forms a portion of winged handle 42 keyed to shaft 34 and held in place by nut 44. Flanges 38 and 40 are spaced apart a distance slightly greater than the thickness of dished element 30 to permit relative rotation of stem 34 and the dished element while preventing relative movement of these elements in an axial direction.

Adjacent the inner end of bore 36 is formed valve seat 46 which is controlled by valve 48 secured to the inner end of stem 34. Passage 49 interconnects with bore 34 adjacent valve set 46 and leads to the outer surface of closure 12. Thus when valve 48 is raised from its seat 46 an unobstructed passage is provided through which any 3 fluid pressure which exists within the pressure vessel may be. bled toattnosphere. Incident to this bleeding of the fiuid pressure from within the vessel an audible signal is produced which indicates that valve 48 is open and accordingly that dished element 30 is not in its innermost position. a

In the embodiment of Figures 6, 7 and 8 a pivotal mechanism is employed to actuate both the valve and the dished element in lieu of the screw threaded arrangement disclosed in Figs. 1, 2 and ,3. As embodied this pivotal mechanism comprises valve stem 50 which is of substantially smaller diameter than bore 36 within which it is disposed and which is provided with longitudinal ribs for guiding it within the bore. The upper end of stem 50 is provided with a bore 55 of predetermined depth for the reception of the end of member 54 which member is threadedly received in boss 56 secured to the upper surface of dished element 30 and provided with a transverse bore 57.

Pivoted to boss 58 which is secured to the upper surface of closure 12 are parallel links 60 which are bored to receive pins 62 extending laterally from this boss 58. The parallel links 60 extend through openings 64 provided in dished element 30 and have their upper ends pivotally connected to lever 66 by pin 58. Depending from this lever are two spaced parallel cars 70 which are pivoted to boss 56 by pin 72. The pin 72 extends through bore 57 provided in the boss and is penetrated by member 54 thereby positively retaining the pin in place.

Through the arrangement of this embodiment it will readily be seen that when lever 66 is in the position indicated by full lines in Fig. 6 dished element 30 and valve stem 50 are moved to their extreme position toward closure 12 whereby the valve occupies its closed position and dished element 30 is effective to cam split ring 24 outwardly into its operative or closure locking position. The relation of valve 48 with respect to dished element 30 can be adjusted by threading member 54 into or out of boss 56 so that simultaneous closing of valve 48 and expansion of split ring 24 into its operative position can be accurately regulated. When lever 66 occupies its dotted line position, shown in Fig. 6, dished element 30 will be moved away from closure 12 permitting split ring 24 to contract to its inoperative position, shown in Fig. 4, and member 54 will be withdrawn from the end of bore 55 permitting any pressure which exists within the vessel to unseat valve 48 and be relieved through the annular passage surrounding stem 50. In the embodiment of Figs. 6, 7 and 8 it is not necessary to provide a separate passage for the relief of this pressure since valve stem 50 is sufficiently smaller than bore, 36 so that this pressure may be relieved through the annular passage surrounding the valve stem.

In operation, closure 12 is pivoted about shaft 18 by means of arms 14 from its open to its closed position within seat means 10 and where gasket 17 engages the inner surface of the seat means to provide an effective fluid tight seal. Dished element 30 is then moved toward closure 12 either by manipulation of winged handle 42, which threads stem 34 into the closure, or by the manipulation of the lever 66 from itsdotted line to its full line position as disclosed in Fig. 6. Movement of dished element 30 toward closure 12 results in expanding split ring 24 from its inoperative position shown in Fig. 4 to its operative position shown in Fig. and where it is positioned between surface 28 and shoulder 22 thereby effectively locking closure 12 within seat means 10. Simultaneously with the movement of dishedv element 30 toward closure 12 valve 4815 moved toward valve seat 46 and when the split ring'is'in its operative position this valve is in fluid tight engagement with its seat.

When it is desired to remove the closure from seat means winged handle 42 or lever 66 is manipulated to move dished element 30 away from closure plate 12. This causes a simultaneous withdrawal of dished element 30 from the position where it cams split ring 24 into its operative position and a withdrawal of valve 48 from its closed position. With valve 48 now open any pressure existing within the vessel with which the closure is associated will be immediately relieved.

Split ring 24 will, however, be held in its operative position intermediate surface 28 and shoulder 22 by frictional forces as long as any pressure exists within the vessel tending to force closure 12 outwardly. Thus, even though element 30 is moved to its extreme position away from closure 12 where it no longer cams the split ring into its operative position, the split ring is unable to contract from its operative position where it positively locks closure 12 within the seat means until the pressure within the vessel is completely relieved. Therefore, should the relief of pressure through the relief passage, when valve 48 is open, take considerable time the closure plate cannot be removed until this time has elapsed and the pressure is completely relieved or alternatively should the relief passage become clogged the closure cannot be removed until the pressure within the vessel is completely relieved through some extraneous means. With the organization of this invention injury to an operator incident to opening a pressure vessel closure while there is pressure existing within the vessel is thereby positively eliminated.

While I have illustrated and described two preferred embodiments of my novel closure it is to be understood that such is merely illustrative and not restrictive and that variations and modifications may be made therein without departing from the spirit and scope of the invention. I therefore do not wish to be limited to the precise details set forth but desire to avail myself of such changes and alterations as fall within the purview of my invention.

What I claim is:

l. A closure for a pressure vessel having an outwardly tapered inner wall forming an opening therein, a closure plate removably fitted within this wall and having the inner portion of its periphery generally complementary to said wall, the outer portion of the periphery of the closure plate being relieved thereby forming an outwardly facing shoulder, a split ring disposed about said outer portion and normally contracted to a position out of engagement with said vessel wall with its end remote from the outer end of the closure plate resting against said shoulder, the inner wall of said vessel being provided with an annular relieved portion forming a shoulder generally parallel with and axially spaced from the first mentioned shoulder in the direction toward the outer end of the opening, the spacing between said shoulders being such as to snugly but slidably receive said split ring therebetween, adjustable cam means including a dishshaped element telescoped over the outer end of the closure plate and having a camming surface coacting with the split ring and constructed and arranged to expand said split ring to a position intermediate said shoulders upon movement of the cam means axially of the plate thereby preventing removal of said closure from said vessel, and means for effecting such axial movement.

2. A closure as defined in claim 1 including a passage through said closure plate to relieve pressure from said vessel, valve means for controlling fluid flow through said passage, actuator means operative to regulate said valve, said actuator means being interconnected with said dish-shaped element so that closure of the valve will simultaneously result in expanding the split ring into position intermediate said shoulders and opening the valve will simultaneously withdraw the cam means from its ring expanding position.

3. A closure as defined in claim 2 wherein the actuator is a screw threaded member threaded to said closure plate and to which said dish-shaped element is joumaled for axial movement therewith. t

4. A closure as defined in claim 2 wherein the actuator includes a stem member slidable in an axial direction within the closure plate, and to which the dish-shaped element is connected for movement therewith, and a pivoted handle suitably connected to said stem to actuate the same. i

5. A closure for a pressure vessel comprising a disclike closure plate, seat means associated with said vessel and operative to receive said closure plate therewithin in a fluid tight manner, an exhaust passage extending through said closure plate for relieving the fluid pressure within said vessel, valve means for controlling said exhaust passage including a valve stem threaded in said closure plate coaxial thereof and extending from the closure plates outer surface, axial movement of said valve stem within said closure plate effecting opening and closing of said valve, means operative to retain said closure plate within said seat means including a split ring deformable to a position intermediate generally parallel, axially spaced annular surfaces formed on the closure plate and seat means respectively, the spacing of said surfaces being but slightly greater than the corresponding dimension of the ring, said surfaces being so constructed and arranged that when said ring is disposed therebetween said closure plate cannot be withdrawn from said seat means, said split ring being normally contracted to a position free of the surface formed on the seat means, a dished element telescoped over the outer end of the closure plate and having a camming face formed on its periphery and coacting with said ring to expand it into operative position intermediate said surfaces upon axial movement in the valve closing direction and upon axial movement in the opposite direction to withdraw the camming face from said ring expanding position, said dished element being interconnected with said valve stem for axial movement therewith whereby actuation of said valve stem to close the valve will operate the dished element to expand the split ring to its operative position and actuation of said valve stem to open the valve will withdraw the dished element from its ring expanding position.

6. A closure for a pressure vessel comprising a disclike closure plate, sea-t means associated with said vessel and operative to receive said closure plate therewithin in a fluid tight manner, an exhaust passage extending through said closure plate for relieving fluid pressure within said vessel and having a portion thereof coaxial with said closure, valve means for controlling said exhaust passage and including a stem member slidably disposed within said closure plate in an axial direction, means operative to retain said closure plate within said seat means including a split ring deformable to a position intermediate generally parallel, axially spaced annular surfaces formed on the closure plate and seat means respectively, the spacing of said surfaces being but slightly greater than the corresponding dimension of the ring, said surfaces being so constructed and arranged that when said ring is disposed therebetween said closure plate cannot be withdrawn from said seat means, said split ring being normally contracted to a position free of the surface formed on the scat means, a dished element telescoped over the outer end of the closure plate and having a camming face formed on its outer periphery and coacting with said ring to expand it into its operative position intermediate said surfaces upon axial movement in one direction and upon axial movement in the opposite direction to withdraw the camming face from said ring expanding position, a pair of parallel links spaced on either side of a plane containing the axis of the closure plate and pivoted at one end to said closure plate about an axis normal to said plane containing the closure plate axis, a handle pivoted to the other end of said links about an axis parallel to the pivoted axis of said one end, said handle also being pivoted to said dished element about an axis parallel with the aforementioned pivotal axes and disposed inwardly of the pivotal connection of the handle with said links when the latter are disposed so that said last named pivotal connection is in a plane containing the axis of the closure plate, whereby movement of said pivotal handle will effect axial movement of said dished element to operate the split ring, means effectively interconnecting the dished element with the valve stem to effect simultaneous operation of the dished element and the valve.

7. A closure comprising a disc-like plate having its periphery stepped to form a shoulder, a split ring disposed about said plate with one end engaging said shoulder, the inner wall of the split ring being inclined to the periphery of said plate to form a wedge-shaped opening which decreases in the direction of said shoulder with the width of the wide end of the wedge shaped opening when the split ring is fully contracted about the plate being greater than the radial distance the split ring must move to project radially beyond the shoulder, a dished element telescoped over the end of the plate of smaller diameter, the rim of said dished element snugly fitting within the wide end of said wedge-shaped opening when said split ring is contracted to its limit about said plate, the portion of the periphery of said dished element immediately adjacent said rim presenting a surface complementary with the inner surface of said split ring whereby axial movement of said dished element toward said plate will cause said surface to engage the inner wall of the ring and expand the ring outwardly to a point where the ring will extend radially'beyond said shoulder, a valved passage extending through said plate, a stem associated with the valve of said passage and arranged to move axially of said plate with movement toward said plate being effective to close said valve and movement away from said plate being effective to open said valve, said stern member and said dished element being interconnected so that they move toward and away from said plate simultaneously.

8. A closure for a pressure vessel provided with an opening comprising a closure plate removably fitted within said opening and adapted to be seated therewithin in a fluid tight manner, the periphery of said plate being stepped to form an outwardly facing shoulder, a split ring disposed about said plate with one end engaging said shoulder, the inner wall surface of said opening being provided with an inwardly facing shoulder spaced outwardly of the shoulder formed on said plate so that said split ring is slidably but snugly receivable therebetween, said split ring normally being contracted about said plate by its own resilience to a position out of engagement with said vessel, adjustable means operative to expand said split ring outwardly to a position intermediate said shoulders and thereby preventing removal of said closure from said vessel, said adjustable means including an annular cam surface disposed about said closure plate and coacting with said split ring to expand the same upon movement of said surface in a direction axially of said plate, and means for moving said surface axially of said plate.

References Cited in the file of this patent UNITED STATES PATENTS 1,418,530 Burnham June 6, 1922 1,473,408 Richardson et al. Nov. 6, 1923 1,870,195 Harris et al. Aug. 2, 1932 2,226,593 Stroupe et al. Dec. 31, 1940 2,399,327 Cullen Apr. 30, 1946 2,529,645 Winks Nov. 14, 1950 2,596,353 Zollinger May 13, 1952 FOREIGN PATENTS 333,400 Great Britain Aug. 14, 1930 713,502 Germany Nov. 13, 1941 587,289 Great Britain Apr. 21, 1947 

